Improvement in printing-presses



A. CAMPBELL.

PRINTING PRESS.

Wei/z assa 4 flMv/W ttnddi w fitter ANDREW CAMPBELL, or BROOKLYN, NEWYORK.

Letters Patent No. 114,106, dated April 25, v1871.

IMPROVEMENT IN PRINTING-PRESSES.

The Schedule referred to in these Letters Patent and making part of thesame.

1, ANDREW CAMPBELL, of the city of Brooklyn, in the county of Kings. andState of New York, have invented certain Improvements inPrinting-Presses, of which the following is a specification.

Nature and Objects of the Invention.

My invention relates to the feeding mechanism of printing-presses, andconsists in arranging above the feed-table a rock-shaft provided with aweighted arm or arms, and so operated by a cam upon theimpression-cylinder, or other equivalent device, as to cause said arm orarms to bear upon the sheets after they are laid upon the table andadjusted to the feed-guides, and to hold them against displacementduring the interval of time between the withdrawal of the feedguides andthe taking hold of the gripcrs, whereby a more perfect register may besecured.

Description of the Drawing.

Figure I is a side elevation of'the impression-cylinder and feed-tableof aprinting-press, showing the application of my improvement thereto.

Figure II is a plan view of same.

1 Figures III, IV, and V are detail views of weighted evers.

General Description.

A represents the impression-cylinder, and

Bthe feed-table, both of ordinary construction.

0 represents the gripcrs, by which the sheets are clamped to thecylinder, drawn from the feed-table, and carried to the impression. Theyare constructed and operate in a common manner.

1) represents the feed-guides mounted upon a rock: shaft, 1), andoperated by an arm, D, on one end of said rock-shaft, and a cam, D, onone end of the cylinder, this also beinga common device.

E represents the rock-shaft which carries the weighted arms orsheet-holders F. It extends across the press and is located above theplane of the feed-table, and its arms F reach beyond the feed-guides Dso that they may bear upon thesheet when laid against said guides.

The arms F are allowed a small amount of angular movement independent ofthe movementof the rockshaft, by means of a double hub, one part, 1, ofwhich is fixed to the shaft by a set-screw or otherwise, and the other,J, is fixed to the arm the fixed part f having a lateral projection, fand the arm part a corresponding lateral projection, f, whichprojections will engage each other alter the manner of a clutchcouplingand cause the arm to lift from the table when the shaft is rotated inone direction, and allow the arm to rest its weight upon the table whenthe shaft is rotated in the opposite direction.

The requisite movement of the shaft to rest the arms upon the table .isobtained by an arm, Gr, upon one end thereof, engaging with a cam, G,upon the end of the cylinder, its return movement to raise the arm beingeffected by counterbalance weight H upon the other end.

The action of said weight is arrested when the arms are raisedsuiiiciently high by a fixed stop, h, against which it strikes.

By the above-described means any degree of pressure upon the sheetnecessary to properly hold it against displacement may be obtained bysimply adjusting the weight of the arms.

The relative position and form of the cams D and G is so adjusted thatthe arms will be made to bear upon the sheet just before the feed-guidesare lifted, and to continue so to bear until after the gripcrs take holdof the sheet, thus insuring the perfect register of the sheet.

It is obvious that the arms can be so made as to bear upon the sheetswith a spring pressure instead of simply by weight, but as the latterpressure can be more accurately and easily adjusted I consider itpreferable.

To add to the friction of the arms F upon the upper surface of the sheetthey may be provided with pads I of India rubber or cloth. as shown inFigs. III and IV.

Claim.

forth.

A. CAMPBELL.

Witnesses:

J. J. VAIL, W. H. Formosa.

